Conventionally, in the case of transporting bulk grain by using shipping containers, first, bulk grain is filled, at the production district, in container inner bags that are provided along an inner surface of containers. The container inner bags are formed into an elongated rectangular parallelepiped shape and made of synthetic resin, such as vinyl chloride, polyethylene and the like. The containers having the inner bags filled with the bulk grain are then transported to destinations, respectively. Doors of the containers transported are opened and the bulk grain within the inner bags is taken out by cutting out a front portion of the inner bags and transferred to storage facilities.
Further, in Japanese Patent Application First Publication (KOKAI) No. 7-223673, there has been proposed a parallelepiped-shaped container inner bag of a two-piece type that includes a front wall portion and a rear elongated rectangular portion. The front wall portion is cut to form a takeout aperture and then discarded. A new front wall portion is mounted to the rear elongated rectangular portion, whereby the container inner bag can be partly reused.
Specifically, the inner bag is made of synthetic resin and has a generally rectangular parallelepiped shape as shown in FIG. 14. One end portion 201 of the inner bag is formed at its upper part with a content insertion aperture 202 through which a large amount of content can be filled into the inner bag. After taking out the content from the inner bag, the front portion including a broken portion 203 that is cut out to form an opening, is removed from the remaining portion 204 and then a new front portion is fitted to the remaining portion. Thus, the inner bag has a reusable construction.
Such the partly reusable inner bag has been proposed in order to eliminate the following disadvantages of the conventionally used inner bag of an integral-sealing type by adopting a split-mounting structure. Since the conventionally used inner bag must be cut to form an aperture for taking out the content from the inner bag by using a cutting member such as a knife, the inner bag must be discarded once used. It will be required to prepare a new inner bag for the subsequent bulk shipment, causing increase in cost. However, the partly reusable inner bag proposed is constructed such that the portion, i.e., the front portion, is cut to form the content takeout aperture by using the cutting member such as a knife as well as the conventional inner bag. The front portion cut is discarded and then replaced by the new one for reuse of the whole inner bag. Thus, the partly reusable inner bag proposed requires complicated structural elements due to forming and mounting means such as sewing for withstanding the cargo weight (for preventing bulge and deformation of the bag), and further necessitates members required for the partial replacement and the mounting cost thereof.
An object of the present invention is to provide a container inner bag adapted to be repetitively used as a whole in ship transportation and discharge operation of a bulk container for a large amount of grain such as malt.
Another object of the present invention is to provide a container inner bag capable of being easily cleaned.
A further object of the present invention is to provide a container inner bag exhibiting a good installation (mounting and removal) performance.
A still further object of the present invention is to provide a container inner bag having a good performance in insertion and takeout of the content.